Figure 4.

Spectral variations associated with F_v of DCMU-treated PSII CC T. vulcanus at 80 K—comparison of F_o, F₁ and F_m. A, Fluorescence emission spectra measured in response to a train of 450 nm sub-saturating flashes from a pulsed LED recorded during Chl-a fluorescence induction at 80 K; the first spectrum (orange) represents the F_o and the last one represents the F_m condition. B, Area-normalized fluorescence spectra—corresponding to F_o and F_m states. C, The spectral distribution of the calculated F_v/F_m ratio. D, Area-normalized fluorescence emission spectra before and after pre-illumination with a STSF, corresponding to F_o and F₁, respectively. Shaded areas represent the SD of the measurements.